Lamp socket



F. R. REUTTER LAMP SOCKET Nov. 9, 1937.

Filed Oct. 15, 1935 ATTORNEYS Patented Nov. 9, I937 UNETED STATE PATENT OFFICE LAMP SOCKET Application October 15, 1935, Serial No. 45,078

3 Claims. (Cl. 173-362) This invention relates to lamp sockets.

The ordinary lamp socket comprises a shell which containsthe switch mechanism and a cap. For purposes of assembly, repair and the like, the

cap can be readily detached and replaced. It is necessary to have some means for preventing relative rotation of the shell and cap and for detachably locking the cap against removal. In previously known constructions the shell has one or more downwardly facing shoulders, usually formed by punching out the metal. On the inside of the cap are one or more lugs or shoulders which snap over the shell shoulders when the capis assembled, thus locking the cap against endwise movement and hence against removal. To prevent relative rotation the shells have had one or more laterally facing shoulders engaged by lugs or the like on the cap.

In order to enable the two socket parts to be assembled without regard to relative angular position, it has been customary to duplicate the locking elements of the cap in a row around the same.

In one type of cap previously known, a row of locking lugs is formed around the skirt of the cap by punching in the metal. This defac'es and perforates the cap skirt and makes a rather unsightly socket which is objectionable commercially. To obtain the desired locking without defacing the skirt, it has been proposed to make a two-piece cap skirt, the inner piece having the requisite locking elements. This type of construction, however, has proved disadvantageous because it is relatively complicated and. expensive to manu- 3 facture.

It is an object of the present invention to provide a lamp socket of the general type referred to, in which the above mentioned objections are avoided. More particularly, it is an object of the invention to provide a lamp socket in which the cap has an imperforate and undefaced. outer surface and at the same time has a one-piece skirt.

With these general objects and others in view the invention consists of the features, combinations, details of construction and arrangements of parts which will first be described in connection with the accompanying drawing and then more particularly pointed out.

50 In the drawing- Figure 1 is a view in vertical section of a lamp socket constructed in accordance with the invention;

Figure 2 is a bottom plan View of the cap;

55 Fig. 3 is a top plan view of the shell;

Fig. 4 is a sectional view (enlarged) taken on the line 4-4 of Figure 1;

Figure 5 is a fragmentary vertical sectional View (enlarged) of the cap skirt;

Figure '6 is a. fragmentary elevational view of 5 the inside of the cap skirt (similarly enlarged), and

Figures 7 and 8 are views similar to Figures 5 and 6 illustrating a modification.

Referring to the drawing, the lamp socket here 10 illustrated as an example comprises a metal shell [5 and a metal cap Hi. The upper part of the shell is fluted, as at II, the several flutes constituting a plurality of equally spaced recesses. The

lower part of the shell has the usual thread I 8 5 for receiving alight bulb or the like. The upper edge of the shell is cut away, as appears at l9, to form the usual notch for a switch key (not shown).

There is provided releasable locking means for 20 preventing separation of the cap and shell comprising locking shoulders on the shell and c'oopcrating locking lugs on the cap. As here shown as an example, downwardly facing locking shoulders are formed by nibs 20 struck in from the 25 metal of the shell and located in the flutes or recesses l1. As appears more clearly in Figure 1, the sheared edges of these struck-in nibs constitute the locking shoulders. In the particular embodiment here illustrated as an example, there 30 are two of these locking nibs 20 located, respectively, in the two flutes adjacent one side of the key notch l9 and two others located generally diametrically opposite.

The invention in its entirety includes a cap having a one-piece skirt with an imperforate and undefaced outer surface and a continuous and unbroken bottom edge. Inside this skirt, the cap has a plurality of locking elements and in structures embodying the invention to what is now considered the best advantage, the locking elements are in the form of equally spaced lugs and are integral with the cap skirt. Although capable of various constructions, in that here illustrated as an example, the cap it comprises a body portion or dome 2|, a thimble 22 secured thereto and a depending skirt or band 23. The skirt is in one piece, is imperforate and has an undefaced outer surface and an unbroken bottom edge.

Inside the cap skirt are a plurality of locking elements for cooperating with nibs 2|]. These lugs may conveniently be formed from tongues of metal shaved from the inner wall of the skirt and integrally rooted thereto.

In the exemplification illustrated in Figures 1-6, the inner wall of the skirt is in two planes whereby there is provided a downwardly facing shoulder 25 at the junction between the upper, thicker part of the skirt and the lower, thinner portion thereof (Figures 5 and 6). This skirt construction may be attained, for example, by forming a cap blank having an ordinary skirt and stripping metal from the inner wall thereof to give the offset planes and the shoulder 25. Inside the skirt are a plurality of locking lugs 26 formed from tongues of metal shaved from the metal of the inner wall of the skirt and integrally rooted thereto. As appears more clearly in Figures 5 and 6, the shaving operation starts from the shoulder 25 and the tongues are thus shaved from the thicker portion of the skirt 23. As.

shown, the lugs 26 are in the form of beads or curls formed by rolling up the tongues as they are shaved. As appears in Figure 2, the lugs extend around the periphery of the cap, are sub stantially equally spaced, and are equal in number to the flutes l'l. It is to be understood that the several lugs are substantially equidistant from the bottom edge of the cap.

When the cap is assembled on the shell, the nibs 20 or the lugs 26, or both, yield suificiently to permit the lugs to pass the nibs and snap under the shoulders thereof. Thereafter, any normal tendency toward axial separation of cap and shell is prevented by the engagement of lugs 26 against the shoulders of nibs 2B. To disasssemble the cap, pressure on the shell adjacent the key notch [9 will cause sufficient temporary deformation of the shell to displace the adjacent nibs 20 and permit the corresponding lugs 26 to pass by on a tilting movement of the cap. 'Ihereupon the engagement of the locking elements at the opposite side is readily released.

With the construction described, the cap is effectively locked on the shell and at the same time the particular lug construction permits an undefaced cap skirt and a one-piece construe tion. With lugs 26 duplicated around the periphery of the cap skirt as shown, the cap may be assembled without regard to its relative angular position.

In the modification illustrated in Figures '7 and 8, the cap skirt 2! is like cap skirt 23 except that the shoulder 25 is omitted and the tongues of metal which form lugs 28 are shaved from the skirt wall starting at the bottom edge thereof.

What is claimed is:

1. In a lamp socket, and in combination, a metal shell having its upper portion fluted, a plurality of downwardly facing locking shoulders on said shell and located in the flutes thereof, a metal cap having a top portion and a depending skirt for taking over the upper end of the shell, and a plurality of equally spaced locking lugs, for cooperating with said shoulders, located inside said skirt and formed of tongues of metal shaved from the inner Wall of the skirt and integrally rooted thereto.

2. In a lamp socket, and in combination, a metal shell having its upper portion formed with a plurality of recesses, locking nibs located in said recesses, a metal cap having a top portion and a depending skirt for taking over the upper end of the shell, and a plurality of locking lugs, for cooperating with said nibs, located inside said skirt and formed of tongues of metal shaved from the inner Wall of the skirt and integrally rooted thereto.

3. A metal cap for a lamp socket comprising a top portion and a depending skirt, a thimble secured in the top portion, the skirt having an internal shoulder, and a plurality of locking lugs formed from tongues of metal shaved from the inner wall of said skirt, starting from said shoulder, and integrally rooted thereto.

FREDERICK R. REUT'I'ER. 

